8/13/2019 Evaporation Process

1/8

Evaporation ProcessBy:

NORAINI BINTI SAIDON

2011293652

NURSYAFINAZ BINTI JAAFAR2011212654

NUR AFIQAH BINTI AB RAZAK

2011670804

8/13/2019 Evaporation Process

2/8

INTRODUCTION

Evaporation (conversion of liquid water into water vapor) is aunique hydrologic process that couples the dynamics of waterand energy cycles over the Earths surface.

The process of evaporation involves the vaporization of aliquid. However, it should be noted that a key distinction forevaporation is that it only happens at the surface of the liquid.

Additionally, evaporation is considered to be part of a phase

transition. This phase transition refers to how molecules in aliquid or water state suddenly become gaseous or suddenlyturn to water vapor.

8/13/2019 Evaporation Process

3/8

8/13/2019 Evaporation Process

4/8

Design of evaporation plants requires consideration of numerous, and sometimes

contradictory, requirements. The most important requirements are as follows:

Product characteristics, including heat sensitivity, viscosity, corrosiveness,

foaming tendency, fouling and precipitation, boiling behavior

Capacity and operation data, including quantities, concentrations,

temperatures, annual operating hours, change of product, controls automation.

Required operating media, such as steam, cooling water, electric power,

cleaning agents, spare parts

Capital and other financial costs

Personnel costs for operation and maintenance

Standards and conditions for manufacture, delivery, acceptance

Choice of materials of construction and surface finishes

Site conditions, such as space, climate (for outdoor sites), connections for

energy and product, service platforms

Legal regulations covering safety, accident prevention, sound emissions,

environmental requirements

8/13/2019 Evaporation Process

5/8

Application evaporation process in

industry The solution flows inside the tubes. A special liquid distribution system at the top

ensures equal liquid feed to each tube and ensures

an even liquid film is obtained (on the

circumference).

The liquid flow per tube is called the wetting rate.

The higher feed concentrations require higherwetting rates to prevent over concentration and

fouling.

The liquid flow per tube is called the wetting rate.

The higher feed concentrations require higher

wetting rates to prevent over concentration and

fouling.

The generated vapour by the evaporation is then

separated from the concentrated liquid at the

bottom of the vessel and goes through a droplet

separator which can be either integrated into the

evaporator shell or separated with a vapour

connection and a highly efficient cyclone inlet.

Falling film

8/13/2019 Evaporation Process

6/8

Forced circulation

The heated solution then evaporates

by flashing in the vessel.

This type of evaporator is welladapted for viscous products and

high fouling rate solutions, solutions

with suspended solids and solutions

close to crystallization.

The system is a combination of a heat

exchanger, for product heating, and a

flash vessel.

A high flow pump circulates the

solution to be evaporated inside the

heater where it is heated a few

degrees over the boiling temperature

by steam or another heating fluid.

8/13/2019 Evaporation Process

7/8

Horizontal wetted tube The evaporated solution flows around the outsideof the tubes in a horizontal tube while the heating

fluid flows through the inside of the tubes.

The advantages of this type of evaporator:

Utilises heat from either steam or hot fluid in

circulation

The space within the tube bundle allows the

evaporated vapours to flow around the tubes

at low velocity and enables a very low

evaporation temperature

Low risk of liquid priming

Easy mechanical cleaning of the outside tube

surface and possibility of tube bundle

dismounting (for limited heat exchange

surface)

Large choice of manufacturing materials

8/13/2019 Evaporation Process

8/8

Conclusion

The process of evaporation involves the vaporization of aliquid. However, it should be noted that a key distinction for

evaporation is that it only happens at the surface of the

liquid. A major requirement of the evaporation process is to

maintain the quality of the liquid during evaporation and toavoid heat damage to the concentrate. Understanding the

process of evaporation has been helping countless

industries and municipalities counter evaporation of limited

water supplies, improve manufacturing efficiency and

maintain more cost effective means of doing business.